JPH04117150U - waste gate valve - Google Patents
waste gate valveInfo
- Publication number
- JPH04117150U JPH04117150U JP2054391U JP2054391U JPH04117150U JP H04117150 U JPH04117150 U JP H04117150U JP 2054391 U JP2054391 U JP 2054391U JP 2054391 U JP2054391 U JP 2054391U JP H04117150 U JPH04117150 U JP H04117150U
- Authority
- JP
- Japan
- Prior art keywords
- valve
- hbn
- foreign matter
- waste gate
- gate valve
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000002699 waste material Substances 0.000 title claims abstract description 21
- 239000000463 material Substances 0.000 claims abstract description 20
- 238000000576 coating method Methods 0.000 claims abstract description 15
- 239000011248 coating agent Substances 0.000 claims abstract description 14
- 229910052582 BN Inorganic materials 0.000 claims abstract description 4
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 claims abstract description 4
- 238000005260 corrosion Methods 0.000 abstract description 4
- 230000007797 corrosion Effects 0.000 abstract description 4
- 239000004071 soot Substances 0.000 description 8
- 238000009825 accumulation Methods 0.000 description 4
- 229910010293 ceramic material Inorganic materials 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000010410 layer Substances 0.000 description 3
- 239000005871 repellent Substances 0.000 description 3
- 239000011347 resin Substances 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- 230000001133 acceleration Effects 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 239000004809 Teflon Substances 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 239000003518 caustics Substances 0.000 description 1
- 238000003776 cleavage reaction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 239000003779 heat-resistant material Substances 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 230000007017 scission Effects 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
Landscapes
- Supercharger (AREA)
- Physical Vapour Deposition (AREA)
Abstract
(57)【要約】
【目的】 ウェイストゲートバルブに異物が付着・堆積
して、バルブが腐食したり、シール不良を起こしたりす
ることを防止できる。
【構成】 熱膨張係数が−４〜＋７×１０-6／℃の弁体
母材１ａを用い、その表面にｈＢＮ（六方晶窒化ホウ
素）の被膜１ｂを形成する。ｈＢＮ被膜１ｂの表面に異
物５が付着すると、バルブ自体の開閉運動や振動によ
り、異物５が付着した部分１ｃだけが薄く剥離して落下
し、異物が排除される。
(57) [Summary] [Purpose] It is possible to prevent foreign matter from adhering to or accumulating on the waste gate valve, causing valve corrosion or seal failure. [Structure] A valve body base material 1a having a thermal expansion coefficient of -4 to +7×10 -6 /°C is used, and a coating 1b of hBN (hexagonal boron nitride) is formed on its surface. When the foreign matter 5 adheres to the surface of the hBN coating 1b, only the portion 1c to which the foreign matter 5 has adhered is peeled off and falls due to the opening/closing movement or vibration of the valve itself, and the foreign matter is removed.
Description
【０００１】0001
本考案はターボチャージャの排気バイパスバルブとして用いるウェイストゲー トバルブに関する。 This invention is a waste gauge used as an exhaust bypass valve of a turbocharger. Regarding tovalve.
【０００２】0002
ウェイストゲートバルブは、ターボチャージャの排気バイパスバルブであり、 加給圧が設定した圧力を越えることを防止し、タービン流入排気ガスを、タービ ン出口にバイパスしてタービン出力を制御し、過給圧をコントロールするもので ある。 A wastegate valve is an exhaust bypass valve for a turbocharger. Prevents boost pressure from exceeding the set pressure and directs exhaust gas flowing into the turbine. Bypassed to the engine outlet to control the turbine output and boost pressure. be.
【０００３】 通常、ウェイストゲートバルブは、過給圧コントロール・アクチュエータに連 結され、設定以上の過給圧になると開放されるしくみになっている。 図３（ａ）（ｂ）で、１はウェイストゲートバルブで、軸２の周りに回動可能 のアーム３に取付けられ、バルルブシート４に密着した同図（ａ）の閉弁状態又 はバルブシート４から離れた同図（ｂ）の開弁状態をとるように構成されている 。0003 The wastegate valve is usually connected to a boost pressure control actuator. The mechanism is such that it is connected and opened when the boost pressure exceeds the set value. In Figures 3(a) and (b), 1 is a waste gate valve, which can be rotated around axis 2. The valve is attached to the arm 3 of the valve and is in close contact with the valve seat 4, as shown in FIG. is configured to assume the open state of the valve shown in FIG. .
【０００４】 他の従来技術として実開昭６４−４１６０６号公報記載の内燃機関用エンジン バルブ（吸・排気弁）が公知である。このエンジンバルブは、表面にテフロン等 の樹脂材料被膜を形成し、樹脂材料被膜の揆水性や揆油性を利用することでバル ブ表面にカーボンが付着推積しないようにしている。0004 Another prior art is an internal combustion engine described in Japanese Utility Model Application Publication No. 64-41606. Valves (intake/exhaust valves) are known. This engine valve has Teflon etc. on the surface. By forming a resin material film and utilizing the water-repellent and oil-repellent properties of the resin material film, This prevents carbon from accumulating on the surface.
【０００５】[0005]
前記従来技術のうち、前者のウェイストゲートバルブは、排気バイパスを開閉 するものであるが、その表面にすす等の異物が付着・堆積し、それが排気ガス中 のＨＣｌ，Ｈ2 ＳＯ4 ，ＨＮＯ3 等を吸着して弁体母材を腐食させることが知ら れている。図４に符号５で示すのはウェイストゲートバルブ１に堆積した異物、 符号６で示す黒点は弁体母材の腐食部を示す。又、すす等がウェイストゲートバ ルブのシール部に付着すると、それを噛み込んで図５のようにシール不良を起こ すことがある。図５に符号７で示すのはウェイストゲートバルブ１のシール部に 付着したすす等の異物を示す。Among the conventional technologies, the former waste gate valve opens and closes the exhaust bypass, but foreign matter such as soot adheres and accumulates on the surface of the waste gate valve, which causes HCl, H 2 SO 4 , and HNO in the exhaust gas. It is known that it adsorbs substances such as No. 3 and corrodes the base material of the valve body. In FIG. 4, reference numeral 5 indicates foreign matter deposited on the waste gate valve 1, and black dots indicated by reference numeral 6 indicate corroded parts of the valve body base material. Furthermore, if soot or the like adheres to the seal portion of the waste gate valve, it may become trapped and cause a seal failure as shown in FIG. In FIG. 5, reference numeral 7 indicates foreign matter such as soot attached to the seal portion of the waste gate valve 1.
【０００６】 このようにウェイストゲートバルブにすす等の異物が付着・堆積することを防 止するために、前記従来技術のうちの後者の技術を施すことが考えられるが、テ フロン等の揆水性樹脂材料は３００〜４００℃以上の高温使用では、溶融や変質 を生じるため、すす等の付着・堆積を防止できない。 そこで、本考案は排気ガスの開閉という高温使用において、すす等の異物の付 着・堆積を防止できるウェイストゲートバルブを提供することを目的とする。[0006] This prevents foreign matter such as soot from adhering to and accumulating on the waste gate valve. In order to prevent Water-repellent resin materials such as fluorocarbons may melt or change in quality when used at high temperatures of 300 to 400 degrees Celsius or higher. It is not possible to prevent the adhesion and accumulation of soot etc. Therefore, the present invention was developed to avoid the presence of foreign substances such as soot during high-temperature use such as opening and closing the exhaust gas. The purpose of the present invention is to provide a waste gate valve that can prevent deposition and deposition.
【０００７】[0007]
上記目的を達成するために、本考案のウェイストゲートバルブは、熱膨張係数 が−４〜＋７×１０-6／℃の弁体母材（１ａ）を用い、その表面にｈＢＮ（六方 昌窒化ホウ素）の被膜（１ｂ）を形成したことを特徴とする。In order to achieve the above object, the wastegate valve of the present invention uses a valve body base material (1a) with a thermal expansion coefficient of -4 to +7 x 10 -6 /°C, and the surface thereof is made of hBN (hexagonal boron nitride). ) is formed.
【０００８】[0008]
ｈＢＮ被膜に異物が付着・堆積したとしても、ｈＢＮ被膜はその一部が薄い層 状に剥離するへき開性があるため、異物ごとｈＢＮ被膜の表層部がはがれ、ウェ イストゲートバルブから外れて、ｈＢＮ被膜は新しい表面が出る。 又、弁体母材の熱膨張係数がｈＢＮの熱膨張係数１〜２×１０-6／℃に近いた め、高温使用時にｈＢＮ被膜にクラックや剥離を生じない。Even if foreign matter adheres to or accumulates on the hBN coating, the hBN coating has a cleavage property that causes part of it to peel off into a thin layer, so the surface layer of the hBN coating peels off along with the foreign matter and comes off from the waste gate valve, and the hBN coating is removed. A new surface appears. Furthermore, since the coefficient of thermal expansion of the valve body base material is close to that of hBN, which is 1 to 2×10 −6 /° C., the hBN coating does not crack or peel when used at high temperatures.
【０００９】[0009]
図１の実施例において、１はウェイストゲートバルブで、セラミック材料であ るＳｉ3 Ｎ4 （窒化ケイ素）の弁体母材１ａの表面にｈＢＮ（六方昌窒化ホウ素 ）の被膜１ｂが形成されている。Ｓｉ3 Ｎ4 とｈＢＮの熱膨張係数はそれぞれ３ 〜４×１０-6／℃と１〜２×１０-6／℃であり、近い値である。In the embodiment shown in FIG. 1, reference numeral 1 denotes a waste gate valve, in which a coating 1b of hBN (hexagonal boron nitride) is formed on the surface of a valve body base material 1a made of Si 3 N 4 (silicon nitride), which is a ceramic material. . The thermal expansion coefficients of Si 3 N 4 and hBN are 3 to 4×10 −6 /°C and 1 to 2×10 −6 /°C, respectively, which are close values.
【００１０】 異物がｈＢＮ被膜の表面に付着していない状態を図１（ｂ）に示すが、同図（ ｃ）のように異物５が付着して、ウェイストゲートバルブ１の開閉運動や振動に よる加速度がかかると、同図（ｄ）のように異物５が付着した部分１ｃだけが薄 く剥離して落下するため、異物がスェイストゲートバルブ表面から排除される。 ウェイストゲートバルブ１の弁体母材１ａとしては、ｈＢＮと熱膨張係数が近 い材料を用いればよく、他のセラミック材料として熱膨張係数が２．８〜３．３ ×１０-6／℃のＳＩＡＬＯＮや、熱膨張係数が約４×１０-6／℃である炭化ケイ 素（ＳｉＣ）を使用することができる。FIG. 1B shows a state in which no foreign matter is attached to the surface of the hBN coating, but as shown in FIG. When acceleration is applied, only the portion 1c to which the foreign matter 5 has adhered is thinly peeled off and falls, as shown in FIG. As the valve body base material 1a of the waste gate valve 1, a material having a coefficient of thermal expansion close to that of hBN may be used, and other ceramic materials include SIALON having a coefficient of thermal expansion of 2.8 to 3.3 × 10 -6 /°C. Alternatively, silicon carbide (SiC) having a coefficient of thermal expansion of about 4×10 −6 /° C. can be used.
【００１１】 次に本考案のウェイストゲートバルブの製造方法の一例を図２に基いて説明す る。セラミック材料をウェイストゲードバルブの形状に形成したグリーンボディ （焼結前の成形体）１ａ′を台８に載せ、グリーンボディ１ａ′の周囲をｈＢＮ の板９，１０で囲み、更にグラファイト又はＳｉ3 Ｎ4 等の約１７００℃に耐え る耐熱材の治具１１，１２に入れて、Ｎ2 雰囲気下で約１７００℃４時間の加熱 をする。この間にグリーンボディ１ａ′は焼結が進んでシンタードボディ（焼結 体）に変化する。同時にｈＢＮが高温により蒸発して、その一部が弁体母材表面 に付着し、ｈＢＮ層が生成される。セラミック材料が焼結を完了し、室温まで冷 却される間にｈＢＮ層は更に厚みを増している。Next, an example of a method for manufacturing the waste gate valve of the present invention will be explained based on FIG. 2. A green body 1a' (a molded body before sintering) made of a ceramic material formed into the shape of a wastegade valve is placed on a table 8, and the green body 1a' is surrounded by hBN plates 9 and 10, and then graphite or Si 3 It is placed in jigs 11 and 12 made of a heat-resistant material such as N 4 that can withstand about 1700° C., and heated at about 1700° C. for 4 hours in an N 2 atmosphere. During this time, the green body 1a' progresses in sintering and changes into a sintered body. At the same time, hBN evaporates due to the high temperature, and a part of it adheres to the surface of the valve body base material, forming an hBN layer. The hBN layer becomes even thicker while the ceramic material completes sintering and cools to room temperature.
【００１２】 なお、蒸着材料としてのｈＢＮは、上述のようにｈＢＮの板９，１０の代りに 、ｈＢＮをスプレー等で台８の上面や治具１２の内面に吹きつけたものでもよい 。 ところで、上記実施例では、弁体母材１ａの表面の全面にｈＢＮ被膜１ｂを形 成したが、必ずしも全表面にｈＢＮ被膜を形成する必要はなく、例えばウェイス トゲードバルブの弁体シール面だけとか、排気ガスが直接当る部位のみに限定し てもよい。0012 Note that hBN as the vapor deposition material can be used instead of the hBN plates 9 and 10 as described above. , hBN may be sprayed onto the top surface of the table 8 or the inner surface of the jig 12. . By the way, in the above embodiment, the hBN coating 1b is formed on the entire surface of the valve body base material 1a. However, it is not necessarily necessary to form an hBN film on the entire surface, for example, Limit it to only the valve body sealing surface of the togged valve, or only to the parts that are directly exposed to exhaust gas. It's okay.
【００１３】 また、ウェイストゲートバルブの他に、排気切替弁においても、弁体母材にセ ラミック等の熱膨張係数の小さい材料を用い、その表面にｈＢＮ被膜を形成する ことで、鉛分やいおう分を含むすす等の異物の堆積を防止し、母材の腐食を防止 できる。 更にまた、内燃機関のエンジンバルブについても、その傘部にｈＢＮ被膜を形 成することにより、カーボン等のデポジットの堆積を抑制し、エンジンの吸・排 気効率の向上（出力の向上）やレスポンスの向上、更には排気ガス中のＨＣやす すが減少するという効果が期待できる。[0013] In addition to wastegate valves, exhaust switching valves also have a Using a material with a small coefficient of thermal expansion such as lamic, an hBN film is formed on its surface. This prevents the accumulation of foreign substances such as soot containing lead and sulfur, and prevents corrosion of the base material. can. Furthermore, hBN coatings are formed on the caps of engine valves for internal combustion engines. By doing so, it suppresses the accumulation of deposits such as carbon and improves engine intake and exhaust. Improving exhaust gas efficiency (improving output) and response, as well as reducing HC in exhaust gas. This can be expected to have the effect of reducing
【００１４】[0014]
本考案のウェイストゲートバルブは、弁体母材の腐食の原因となるＨＣｌ，Ｈ 2 ＳＯ4,ＨＮＯ3 等の酸及び鉛分等の腐食性物質を含む異物が堆積しにくいため 、弁体母材の腐食が抑制され耐久性が向上する。 また、ウェイストゲートバルブのシール部への異物の付着が抑制され、弁体の シール性が向上するため、車輛の加速性がよくなる。 The waste gate valve of the present invention is free from HCl and H, which cause corrosion of the base material of the valve body. 2 S.O.Four,HNO3Because it is difficult for foreign substances including acids such as and corrosive substances such as lead to accumulate. , corrosion of the valve body base material is suppressed and durability is improved. In addition, the adhesion of foreign matter to the seal part of the waste gate valve is suppressed, and the valve body The improved sealing performance improves vehicle acceleration.
【００１５】 更にまた、ウェイストゲートバルブ表面への異物の堆積が抑制されて、バルブ の慣性質量が小さいまゝで維持されるため、ウェイストゲートバルブのレスポン スが低下する虞がない。[0015] Furthermore, the accumulation of foreign matter on the wastegate valve surface is suppressed, and the valve The inertial mass of the wastegate valve remains small, which improves the response of the wastegate valve. There is no risk of the performance decreasing.
【図１】（ａ）は本考案の実施例の一部縦断面図、
（ｂ）は同図（ａ）のＡ部を拡大した図、（ｃ）は同図
（ｂ）のｈＢＮ被膜に堆積物が付着した態様を示す図、
（ｄ）は同図（ｃ）の堆積物がｈＢＮ被膜の一部分と共
に剥離した態様を示す図である。FIG. 1 (a) is a partial longitudinal sectional view of an embodiment of the present invention;
(b) is an enlarged view of part A in (a) of the same figure, (c) is a view showing a state in which deposits have adhered to the hBN coating of (b) of the same figure,
(d) is a diagram showing a state in which the deposit shown in (c) of the same figure has been peeled off together with a portion of the hBN coating.
【図２】本考案のウェイストゲートバルブの製造方法の
一例を説明する縦断面図である。FIG. 2 is a longitudinal sectional view illustrating an example of the method for manufacturing the wastegate valve of the present invention.
【図３】ウェイストゲードバルブまわりの機構の一部縦
断面図で、（ａ）は閉弁状態、（ｂ）は開弁状態を示
す。FIG. 3 is a partial vertical cross-sectional view of a mechanism surrounding the wastegade valve, with (a) showing the valve closed state and (b) showing the valve open state.
【図４】従来のウェイストゲートバルブに異物が付着・
堆積した状態を説明する一部縦断面図である。[Figure 4] Foreign matter attached to the conventional waste gate valve
FIG. 3 is a partial vertical cross-sectional view illustrating a deposited state.
【図５】従来のウェイストゲートバルブのシール部にす
す等の異物が付着して噛み込んだ状態を示す一部縦断面
図である。FIG. 5 is a partial longitudinal cross-sectional view showing a state in which foreign matter such as soot has adhered to and become stuck in the seal portion of a conventional waste gate valve.
１ ウェイストゲートバルブ １ａ 弁体母材 １ｂ ｈＢＮ被膜 1 Waste gate valve 1a Valve body base material 1b hBN coating
Claims (1)
弁体母材（１ａ）を用い、その表面にｈＢＮ（六方晶窒
化ホウ素）の被膜（１ｂ）を形成したことを特徴とする
ウェイストゲートバルブ。Claim 1: A valve body base material (1a) having a thermal expansion coefficient of -4 to +7×10 -6 /°C is used, and a coating (1b) of hBN (hexagonal boron nitride) is formed on its surface. Features a waste gate valve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2054391U JPH04117150U (en) | 1991-04-01 | 1991-04-01 | waste gate valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2054391U JPH04117150U (en) | 1991-04-01 | 1991-04-01 | waste gate valve |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04117150U true JPH04117150U (en) | 1992-10-20 |
Family
ID=31906601
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2054391U Pending JPH04117150U (en) | 1991-04-01 | 1991-04-01 | waste gate valve |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04117150U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2015048837A (en) * | 2013-09-04 | 2015-03-16 | トヨタ自動車株式会社 | Control device of waste gate valve |
| US9376930B2 (en) | 2013-10-30 | 2016-06-28 | Hyundai Motor Company | Waste gate valve |
-
1991
- 1991-04-01 JP JP2054391U patent/JPH04117150U/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2015048837A (en) * | 2013-09-04 | 2015-03-16 | トヨタ自動車株式会社 | Control device of waste gate valve |
| US9376930B2 (en) | 2013-10-30 | 2016-06-28 | Hyundai Motor Company | Waste gate valve |
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